But according to celebrity fitness pioneer Jackie Warner, who is known for sculpting Hollywood’s best bodies, 31-year-old Simpson wouldn’t have been panned before the birth of baby Maxwell Drew Johnson, if she HAD made the effort to work out during the nine months of pregnancy.

“The body is meant to move and be active and we are in this age that we are inactive a majority of the week and that’s a huge mistake,” the host of Bravo’s Thintervention with Jackie Warner told Celebuzz.

“If you’re working out during your pregnancy, the pregnancy not only goes better, the baby is healthier, and the weight falls off much quicker. It’s really really important to work out during pregnancy.

“I have trained many clients at nearly seven months along, so there really is a lot that you can do.”

“Well first of all, the same things that you do post-baby are the things that you should be doing pre-baby. You just need to maintain a healthy lifestyle—make sure you’re eating 2 fruits, 3 vegetables, 3 lean proteins, and 2 fats per day, so that it is just a clean diet. Make sure you’re eating your breakfast, your snack, your lunch, your snack, and your dinner, so your insulin levels don’t drop.”

Jessica Simpson’s Baby Shower

Warner added: “Here is the wake up call to America — Harvard did a study four years ago. You shouldn’t be working out 3 days a week, you should have at least 15-20 minutes of an intensity workout everyday of your life!”

Check out more amazing Hollywood post-baby bodies in the video, below.

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